ML25274A140

Supplement to the License Amendment Request to Revise the Licensing and Design Basis to Incorporate the Replacement of Existing Safety-Related Analog Control Systems with a Single Digital Plant Protection System (PPS) - .

ML25274A140
Person / Time
Site:	Limerick
Issue date:	10/01/2025
From:	Para W Constellation Energy Generation
To:	Office of Nuclear Reactor Regulation, Document Control Desk
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ML25274A138	List: ML25274A140
References
Download: ML25274A140 (1)

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200 Energy Way Kennett Square, PA 19348 www.ConstellationEnergy.com 10 CFR 50.90 October 1, 2025 U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 ATTN: Document Control Desk Limerick Generating Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-39 and NPF-85 NRC Docket Nos. 50-352 and 50-353

Subject:

Supplement to the License Amendment Request to Revise the Licensing and Design Basis to Incorporate the Replacement of Existing Safety-Related Analog Control Systems with a Single Digital Plant Protection System (PPS)

- Errata Pages for the Licensing Technical Report

References:

1. Constellation Energy Generation, LLC (CEG) letter to the U.S. Nuclear Regulatory Commission (NRC), "License Amendment Request to Revise the Licensing and Design Basis to Incorporate the Replacement of Existing Safety-Related Analog Control Systems with a Single Digital Plant Protection System (PPS)," dated September 26, 2022 (NRC Agencywide Documents Access and Management System (ADAMS)

Accession No. ML22269A569) 2.

CEG letter to the NRC, "Resubmittal of License Amendment Request to Revise the Licensing and Design Basis to Incorporate the Replacement of Existing Safety-Related Analog Control Systems with a Single Digital Plant Protection System (PPS) -To Address Proprietary Issues with DOE INL HFE Reports 2s," dated September 12, 2023 (ADAMS Accession No. ML23255A095) 3.

CEG letter to the NRC, " Supplement to License Amendment Request to Revise the Licensing and Design Basis to Incorporate the Replacement of Existing Safety-Related Analog Control Systems with a Single Digital Plant Protection System (PPS) - Pivot to Unit 1 PPS First Installation in 2026," dated April 23, 2024 (ADAMS Accession No. ML24114A322) 4.

CEG letter to U.S. NRC, Supplement to License Amendment Request to Revise the Licensing and Design Basis to Incorporate the Replacement of Existing Safety-Related Analog Control Systems with a Single Digital Plant Protection System (PPS)- SyRS, SyDS, FMEA, LTR, AOA, EQRS Revision Update, dated January 26, 2024 (ADAMS Accession No. ML24026A296)

ATTACHMENT 1 TRANSMITTED HEREWITH CONTAINS PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 When separated, the cover letter, Attachment 2, and Attachment 3 are decontrolled.

ATTACHMENT 1 TRANSMITTED HEREWITH CONTAINS PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 When separated, the cover letter, Attachment 2, and Attachment 3 are decontrolled.

LAR Supplement for LTR Errata Pages Docket Nos. 50-352 and 50-353 October 1, 2025 Page 5 In Reference 1 Constellation Energy Generation, LLC (CEG) requested a License Amendment Request (LAR) to facilitate replacement of the Limerick Generating Station, Units 1 and 2 (LGS) existing safety-related analog control systems with a single digital Plant Protection System (PPS) (i.e., the Digital Modernization Project - DMP). In Reference 2, CEG submitted a LAR supplement that replaced in its entirety the original LAR in order to address issues associated with proprietary/non-proprietary information previously submitted.

This supplement provides a revised implementation schedule for the amendments, once approved, that reflect the current planned installation timing and errata sheets for the Licensing Technical Report (LTR).

In Reference 1, CEG stated the proposed TS changes would be implemented prior to start-up from the LGS, Unit 1 Refueling Outage in April 2024 (Li1R20), and the LGS, Unit 2 Refueling Outage in April 2025 (Li2R18). In Reference 3 CEG stated the LGS, Unit 1 PPS installation was pivoted to the LGS, Unit 1 Refueling Outage in April 2026 (Li1R21), and the LGS, Unit 2 Refueling Outage in April 2027 (Li2R19). To reflect the current planned installation timing, CEG proposes the amendments, once approved, be implemented at LGS, Unit 1 prior to startup following the System Installation Outage, and at LGS, Unit 2 prior to startup following the System Installation Outage. This implementation period will provide adequate time for the affected station documents to be revised using the appropriate change control mechanisms.

In Reference 4, CEG transmitted the LTR, Revision 2. Subsequent to the submittal of the LTR, editorial errors were identified. This letter provides marked-up and retyped clean errata sheets of the LTR. Attachment 1 contains Westinghouse Electric Company, LLC (WEC) proprietary document LIM-25-010-P, Update to WCAP-18598, Revision 2, Licensing Technical Report for the Limerick Generating Station Units 1&2 Digital Modernization Project. Attachment 2 contains a non-proprietary version of the document, LIM-25-010-NP, Update to WCAP-18598, Revision 2, Licensing Technical Report for the Limerick Generating Station Units 1&2 Digital Modernization Project. The provided errata sheets in Attachments 1 and 2 supersede the original transmittal of this information in the LTR provided in Reference 4. contains an affidavit signed by WEC, the owner of the proprietary information.

The affidavit sets forth the basis upon which the information may be withheld from public disclosure by the NRC, and they address with specificity the considerations listed in paragraph (b)(4) of 10 CFR 2.390 of the NRCs regulations. WEC requests that the WEC proprietary information contained in Attachment 1 be withheld from public disclosure in accordance with 10 CFR 2.390. Future correspondence with respect to the proprietary aspects of the application for withholding related to WEC proprietary information or the WEC affidavit provided in the applicable Attachment should reference this request letter.

CEG has reviewed the information supporting a finding of no significant hazards consideration, and the environmental consideration, which was previously provided to the NRC in References 1 and 2. CEG has concluded that the information provided in this supplemental letter does not affect the bases for concluding that the proposed license amendments do not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92. In addition, CEG has concluded that the information in this supplemental letter does not affect the bases for concluding that neither an environmental ATTACHMENT 1 TRANSMITTED HEREWITH CONTAINS PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 When separated, the cover letter, Attachment 2, and Attachment 3 are decontrolled.

LAR Supplement for LTR Errata Pages Docket Nos. 50-352 and 50-353 October 1, 2025 Page 5 impact statement nor an environmental assessment needs to be prepared in connection with the proposed amendments.

This supplemental letter contains no regulatory commitments.

If you have any questions regarding this submittal, then please contact Ashley Rickey at Ashley.Rickey@constellation.com.

I declare under penalty of perjury that the foregoing is true and correct. Executed on this 1st day of October 2025.

Respectfully, Wendi E. Para Sr. Manager - Licensing Constellation Energy Generation, LLC Attachments: 1. Update to WCAP-18598, Revision 2, Licensing Technical Report for the Limerick Generating Station Units 1&2 Digital Modernization Project, LIM-25-010-P, Revision 4, dated October 2025 (Proprietary) 2.

Update to WCAP-18598, Revision 2, Licensing Technical Report for the Limerick Generating Station Units 1&2 Digital Modernization Project, LIM-25-010-NP, Revision 4, dated October 2025 (Non-Proprietary) 3.

WEC affidavit for CAW-25-058 for WEC Proprietary Information in cc:

USNRC Region I, Regional Administrator w/ attachments USNRC Project Manager, LGS USNRC Senior Resident Inspector, LGS ATTACHMENT 1 TRANSMITTED HEREWITH CONTAINS PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 When separated, the cover letter, Attachment 2, and Attachment 3 are decontrolled.

Limerick Generating Station, Units 1 and 2 Docket Nos. 50-352 and 50-353 Update to WCAP-18598, Revision 2, Licensing Technical Report for the Limerick Generating Station Units 1&2 Digital Modernization Project, LIM-25-010-P, Revision 4, dated October 2025.

(Proprietary)

ATTACHMENT 1 TRANSMITTED HEREWITH CONTAINS PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 When separated, the cover letter, Attachment 2, and Attachment 3 are decontrolled.

Limerick Generating Station, Units 1 and 2 Docket Nos. 50-352 and 50-353 Update to WCAP-18598, Revision 2, Licensing Technical Report for the Limerick Generating Station Units 1&2 Digital Modernization Project, LIM-25-010-NP, Revision 4, dated October 2025.

(Non-Proprietary)

ATTACHMENT 1 TRANSMITTED HEREWITH CONTAINS PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 When separated, the cover letter, Attachment 2, and Attachment 3 are decontrolled.

©2025 Westinghouse Electric Company LLC. All Rights Reserved Electronically Approved Records Are Authenticated in the Electronic Document Management System Westinghouse Electric Company 1000 Westinghouse Drive Cranberry Township, Pennsylvania 16066 USA Mr. Jerry Segner Principal Project Manager Constellation Energy Generation, LLC Limerick Generating Station 3146 Sanatoga Road Pottstown, PA 19464 jerry.segner@constellation.com Direct Telephone:

(860) 731-6260 E-mail:

shakunma@westinghouse.com Contract:

00800304 Sales Order:

156102 Our Ref:

LIM-25-010-NP, Revision 4 October 1, 2025 CONSTELLATION ENERGY GENERATION LIMERICK UNITS 1 AND 2 DIGITAL MODERNIZATION PROJECT Update to WCAP-18598, Revision 2, Licensing Technical Report for the Limerick Generating Station Units 1&2 Digital Modernization Project

Dear Mr. Segner:

The following provides redline markups to WCAP-18598, Revision 2, Licensing Technical Report for the Limerick Generating Station Units 1&2 Digital Modernization Project, to address CAP IR-2024-11761.

WCAP-18598, Section 3.2.2 is updated as follows:

Three DI621 Digital Input Modules for [

]a,c, Reactor Shutdown Panel inputs, and inputs for fast RPS trip functions (see Section 3.4.1) provides a redline markup of WCAP-18598, Figure 3.2-2.

provides a clean version of WCAP-18598, Figure 3.2-2.

WCAP-18598, Section 9.2 is updated as follows:

The RRCS/DPS is on a dedicateddesignated redundant controller on the DCS network (Drop 4/54).

The following changes to WCAP-18598 were identified during the Licensing Impact review of WNA-ECN-00134-GLIM, Limerick DMP Baseline 6.3 Updates.

WCAP-18598, Section 3.5.13 is updated as follows:

Westinghouse Non-Proprietary Class 3

Westinghouse Non-Proprietary Class 3 Page 2 of 4 Our Ref: LIM-25-010-NP, Revision 4 The 1E isolation devices shown in the figures in Section 3.5 provide 1E electrical isolation that meets the minimum breakdown voltage of at least 600VAC/500VDCRMS.

WCAP-18598, Section 3.4.1 is updated as follows:

[

]a,c provides a redline markup of WCAP-18598, Figure 3.4-1. provides a redline markup of WCAP-18598, Figure 3.4-2.

The following changes to WCAP-18598 were identified during the Licensing Impact review of WNA-ECN-00135-GLIM, Limerick DMP Baseline 6.4 Updates.

WCAP-18598, Section 3.6.2.7 is updated as follows:

"The fail-safe state for the PPS RPS functions is the reactor trip scram condition. The For NSSSS and ECCS, it depends on the specific functions as to whether or not the PPS will fail to the actuate state or fail as-is. actuations are designed to de energize to activate. Should there be a loss of power to a division, the NSSSS functions will activate. ECCS functions are designed to fail as-is. This is to protect the plant from spurious actuation of ECCS functions on loss of power.

The following changes to WCAP-18598 were identified during the Licensing Impact Review of WNA-ECN-00137-GLIM, Limerick DMP Baseline 6.7 Updates.

Westinghouse Non-Proprietary Class 3 Page 3 of 4 Our Ref: LIM-25-010-NP, Revision 4 WCAP-18598, Section 3.5.14.4 is updated as follows:

The PPS interfaces as discussed in Section 3.5 meet the independence criteria of IEEE Std 384-19981. The interfaces discussed in Section 3.5 demonstrate the electrical isolation and functional independence of the PPS to the non-safety interfaces.

This change has been documented in CAP-PIR-2025-2826.

provides a redline markup of WCAP-18598, Figure 3.2-1.

This change has been documented in CAP-PIR-2025-2641.

WCAP-18598, Section 3.4.1 is updated as follows:

[

]a,c provides a redline markup of WCAP-18598, Table A.6.1-1.

provides a redline markup of WCAP-18598, Figure 3.4-3 Attachments 8 - 11 provide clean versions to WCAP-18598, Figures 3.2-1, 3.4-1, 3.4-2, 3.4-3.

If you have any questions or require additional information regarding this transmittal, please feel free to contact me at (860) 731-6260.

Sincerely, WESTINGHOUSE ELECTRIC COMPANY LLC Electronically Approved Author: Matthew A. Shakun Principal Licensing Engineer Reviewer: Warren R. Odess-Gillett Licensing Consultant Reviewer: Steven Merkiel Principal Engineer Approver: Jerrod Ewing Manager, Operating Plants Licensing Attachments:

1.

Redline Figure 3.2-2

2.

Clean Figure 3.2-2

3.

Updated Figure 3.4-1

4.

Updated Figure 3.4-2

5.

Updated Figure 3.2-1

6.

Updated Table A.6.1-1

7.

Updated Figure 3.4-3

8.

Clean Figure 3.4-1

9.

Clean Figure 3.4-2

10. Clean Figure 3.2-1

11. Clean Figure 3.4-3

Westinghouse Non-Proprietary Class 3 Page 4 of 4 Our Ref: LIM-25-010-NP, Revision 4 cc: Constellation Energy Steven Hesse steven.hesse@constellation.com Kayla Marriner kaylalover.marriner@constellation.com Zina Gavin zina.gavin@constellation.com Mark Samselski mark.samselski@constellation.com Ashley Rickey ashley.rickey@constellation.com Westinghouse Electric Company LLC Courtney Frank Parastoo Muse Andrew Lutz Steve Merkiel Andrew Barth

]a,c

[

LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Redline Figure 3.2-2

]a,c

[

LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Clean Figure 3.2-2

[

]a,c Figure 3.4-2 RPS Trip Functions Reactor Vessel Pressure and Reactor Vessel Water Level Westinghouse Non-Proprietary Class 3 - Updated Figure 3.4-2 LIM-25-010-NP, Rev. 4

Table A.6.1-1 LGS Channel Check Eliminations Table/Function (Existing LGS Technical Specifications)

Description Instruments Measure Redundant Processes Function Based on Sensor Value Can be Eliminated 4.3.1.1-1, Function 1a IRM Neutron Flux -

High Yes1 Yes1 Yes1 4.3.1.1-1, Function 1b Inoperative N/A N/A N/A 4.3.1.1-1, Function 2a APRM Neutron Flux -

Upscale (Setdown)

N/A2 N/A2 N/A2 4.3.1.1-1, Function 2b Simulated Thermal Power - Upscale N/A2 N/A2 N/A2 4.3.1.1-1, Function 2c Neutron Flux - Upscale N/A2 N/A2 N/A2 4.3.1.1-1, Function 2d Inoperative N/A N/A N/A 4.3.1.1-1, Function 2e 2-Out-Of-4 Voter Yes1 Yes1 Yes1 4.3.1.1-1, Function 2f OPRM Upscale N/A2 N/A2 N/A2 4.3.1.1-1, Function 3 Reactor Vessel Steam Dome Pressure - High Yes Yes Yes 4.3.1.1-1, Function 4 Reactor Vessel Water Level-Low, Level 3 Yes Yes Yes 4.3.1.1-1, Function 5 Main Steam Line Isolation Valve -

Closure N/A1 N/A1 N/A1 4.3.1.1-1, Function 6 Deleted from technical specifications N/A N/A N/A 4.3.1.1-1, Function 7 Drywell Pressure - High Yes Yes Yes3 4.3.1.1-1, Function 8a Scram Discharge Volume Water Level -

High Level Transmitter Yes Yes Yes LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Updated Table A.6.1-1

Table/Function (Existing LGS Technical Specifications)

Description Instruments Measure Redundant Processes Function Based on Sensor Value Can be Eliminated 4.3.1.1-1, Function 8b Scram Discharge Volume Water Level -

High Float Switch N/A1 N/A1 N/A1 4.3.1.1-1, Function 9 Turbine Stop Valve -

Closure N/A1 N/A1 N/A1 4.3.1.1-1, Function 10 Turbine Control Valve Fast Closure, Trip Oil Yes Yes Yes 4.3.1.1-1, Function 10 Turbine Control Valve Fast Pressure - Low N/A1 N/A1 N/A1 4.3.1.1-1, Function 11 Reactor Mode Switch Shutdown Position N/A1 N/A1 N/A1 4.3.1.1-1, Function 12 Manual Scram N/A N/A N/A 4.3.2.1-1, Function 1a Reactor Vessel Water Level

1) Low, Low, Level 2 1, 2, 3

2) Low, Low, Low -

Level 1 Yes Yes Yes 4.3.2.1-1, Function 1b Deleted from technical specifications N/A N/A N/A 4.3.2.1-1, Function 1c Main Steam Line Pressure - Low Yes Yes Yes 4.3.2.1-1, Function 1d Main Steam Line Flow - High Yes Yes Yes 4.3.2.1-1, Function 1e Condenser Vacuum -

Low Yes Yes Yes 4.3.2.1-1, Function 1f Outboard MSIV Room Yes Yes Yes LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Updated Table A.6.1-1

Table/Function (Existing LGS Technical Specifications)

Description Instruments Measure Redundant Processes Function Based on Sensor Value Can be Eliminated Temperature - High 4.3.2.1-1, Function 1g Turbine Enclosure -

Main Steam Line Tunnel Temperature - High Yes Yes Yes 4.3.2.1-1, Function 1h Manual Initiation N/A N/A N/A 4.3.2.1-1, Function 2a Reactor Vessel Water Level Low - Level 3 Yes Yes Yes 4.3.2.1-1, Function 2b Reactor Vessel (RHR Cut-In 1, 2, 3 Permissive) Pressure -

High Yes Yes Yes 4.3.2.1-1, Function 2c Manual Initiation N/A N/A N/A 4.3.2.1-1, Function 3a RWCS Flow - High Yes1 Yes1 Yes1 4.3.2.1-1, Function 3b RWCS Area Temperature - High Yes Yes Yes 4.3.2.1-1, Function 3c RWCS Area Ventilation Temperature - High Yes Yes Yes 4.3.2.1-1, Function 3d SLCS Initiation N/A1 N/A1 N/A1 4.3.2.1-1, Function 3e Reactor Vessel Water Level Low, Low, - Level 2 Yes Yes Yes 4.3.2.1-1, Function 3f Manual Initiation N/A N/A N/A 4.3.2.1-1, Function 4a HPCI Steam Line Pressure - High Yes Yes Yes LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Updated Table A.6.1-1

Table/Function (Existing LGS Technical Specifications)

Description Instruments Measure Redundant Processes Function Based on Sensor Value Can be Eliminated 4.3.2.1-1, Function 4b HPCI Steam Supply Pressure, Low Yes Yes Yes 4.3.2.1-1, Function 4c HPCI Turbine Exhaust Diaphragm Pressure -

High Yes Yes Yes 4.3.2.1-1, Function 4d/e HPCI Equipment Room Temperature - High Temperature - High Yes Yes Yes 4.3.2.1-1, Function 4f HPCI Pipe Routing Area Temperature - High Yes Yes Yes 4.3.2.1-1, Function 4g Manual Initiation N/A N/A N/A 4.3.2.1-1, Function 4h HPCI Steam Line Pressure Timer N/A N/A N/A 4.3.2.1-1, Function 5a RCIC Steam Line Pressure - High Yes Yes Yes 4.3.2.1-1, Function 5b RCIC Steam Supply Pressure - Low Yes Yes Yes 4.3.2.1-1, Function 5c RCIC Turbine Exhaust Diaphragm Pressure - High Yes Yes Yes 4.3.2.1-1, Function 5d/e RCIC Equipment Room Temperature - High RCIC Equipment Room Temperature - High Yes Yes Yes 4.3.2.1-1, Function 5f RCIC Pipe Routing Area Temperature - High Yes Yes Yes LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Updated Table A.6.1-1

Table/Function (Existing LGS Technical Specifications)

Description Instruments Measure Redundant Processes Function Based on Sensor Value Can be Eliminated 4.3.2.1-1, Function 5g Manual Initiation N/A N/A N/A 4.3.2.1-1, Function 5h RCIC Steam Line Pressure Timer N/A N/A N/A 4.3.2.1-1, Function 6a Reactor Vessel Water Level

1) Low, Low - Level 2 1, 2, 3

2) Low, Low, Low -

Level 1 Yes Yes Yes 4.3.2.1-1, Function 6b Drywell Pressure - High Yes Yes Yes3 4.3.2.1-1, Function 6c North Stack Effluent Radiation - High Yes1 No1 No1 4.3.2.1-1, Function 6d Deleted N/A N/A N/A 4.3.2.1-1, Function 6e Reactor Enclosure Ventilation Exhaust Duct - Radiation - High Yes1 Yes1 Yes1 4.3.2.1-1, Function 6f Deleted N/A N/A N/A 4.3.2.1-1, Function 6g Deleted N/A N/A N/A 4.3.2.1-1, Function 6h Drywell Pressure -

High/ Reactor Pressure -

Low Yes Yes Yes3 4.3.2.1-1, Function 6i Primary Containment Instrument Gas to Drywell Pressure -

Low N/A N/A N/A 4.3.2.1-1, Function 6j Manual Initiation N/A N/A N/A LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Updated Table A.6.1-1

Table/Function (Existing LGS Technical Specifications)

Description Instruments Measure Redundant Processes Function Based on Sensor Value Can be Eliminated 4.3.2.1-1, Function 7a Reactor Vessel Water Level Low, Low - Level 2 Yes Yes Yes 4.3.2.1-1, Function 7b Drywell Pressure - High Yes Yes Yes3 4.3.2.1-1, Function 7c Refueling Area Unit 1 Ventilation Exhaust Duct Radiation - High Refueling Area Unit 2 Ventilation Exhaust Duct Radiation - High Yes1 No1 No1 4.3.2.1-1, Function 7d Reactor Enclosure Ventilation Exhaust Duct Radiation - High Yes1 Yes1 Yes1 4.3.2.1-1, Function 7e Deleted N/A N/A N/A 4.3.2.1-1, Function 7f Deleted N/A N/A N/A 4.3.2.1-1, Function 7g Reactor Enclosure Manual Initiation N/A N/A N/A 4.3.2.1-1, Function 7h Refueling Area Manual Initiation N/A N/A N/A 4.3.3.1-1, Function 1a Reactor Vessel Water Level -

Low Low Low, Level 1 Yes Yes Yes 4.3.3.1-1, Function 1b Drywell Pressure - High Yes Yes Yes3 4.3.3.1-1, Function 1c Reactor Vessel Pressure

- Low Yes Yes Yes 4.3.3.1-1, Function 1d Manual Initiation N/A N/A N/A LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Updated Table A.6.1-1

Table/Function (Existing LGS Technical Specifications)

Description Instruments Measure Redundant Processes Function Based on Sensor Value Can be Eliminated 4.3.3.1-1, Function 2a Reactor Vessel Water Level -

Low Low Low, Level 1 Yes Yes Yes 4.3.3.1-1, Function 2b Drywell Pressure - High Yes Yes Yes3 4.3.3.1-1, Function 2c Reactor Vessel Pressure

- Low Yes Yes Yes 4.3.3.1-1, Function 2d Injection Valve Differential Pressure -

Low (Permissive)

Yes Yes Yes 4.3.3.1-1, Function 2e Manual Initiation N/A N/A N/A 4.3.3.1-1, Function 3a Reactor Vessel Water Level -

Low Low, Level 2 Yes Yes Yes 4.3.3.1-1, Function 3b Drywell Pressure - High Yes Yes Yes3 4.3.3.1-1, Function 3c Condensate Storage Tank Level - Low Yes Yes Yes 4.3.3.1-1, Function 3d Suppression Pool Water Level - High Yes Yes Yes 4.3.3.1-1, Function 3e Reactor Vessel Water Level -

High, Level 8 Yes Yes Yes 4.3.3.1-1, Function 3f Manual Initiation N/A N/A N/A 4.3.3.1-1, Function 4a Reactor Vessel Water Level -

Low Low Low, Level 1 Yes Yes Yes 4.3.3.1-1, Function 4b Drywell Pressure - High Yes Yes Yes3 LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Updated Table A.6.1-1

Table/Function (Existing LGS Technical Specifications)

Description Instruments Measure Redundant Processes Function Based on Sensor Value Can be Eliminated 4.3.3.1-1, Function 4c ADS Timer N/A N/A N/A 4.3.3.1-1, Function 4d Core Spray Pump Discharge Pressure -

High YesN/A4 N/A4Yes N/A4Yes 4.3.3.1-1, Function 4e RHR LPCI Mode Pump Discharge Pressure -

High N/A4Yes N/A4Yes N/A4 Yes 4.3.3.1-1, Function 4f Reactor Vessel Water Level - Low, Level 3 Yes Yes Yes 4.3.3.1-1, Function 4g Manual Initiation N/A N/A N/A 4.3.3.1-1, Function 4h ADS Drywell Pressure Bypass Timer N/A N/A N/A 4.3.7.5-1, Function 1 Reactor Vessel Pressure Yes Yes Yes 4.3.7.5-1, Function 2 Reactor Vessel Water Level Yes Yes Yes 4.3.7.5-1, Function 3 Suppression Chamber Water Level Yes Yes Yes 4.3.7.5-1, Function 4 Suppression Chamber Water Temperature Yes Yes Yes 4.3.7.5-1, Functions 5, 7 -

10 Deleted N/A N/A N/A 4.3.7.5-1, Function 6 Primary Containment Pressure Yes Yes Yes 4.3.7.5-1, Function 11 Primary Containment Post LOCA Radiation Monitors Yes1 Yes1 Yes1 4.3.7.5-1, Function 12 North Stack Wide Range Accident Monitor Yes1 Yes1 Yes1 LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Updated Table A.6.1-1

Table/Function (Existing LGS Technical Specifications)

Description Instruments Measure Redundant Processes Function Based on Sensor Value Can be Eliminated 4.3.7.5-1, Function 13 Neutron Flux Yes1 Yes1 Yes1 1.

These are contact inputs. Those rows with Yes across with this note are required in technical specifications to have a channel check. Those with N/A across the row with this note do not require a channel check. Those contact inputs that require a channel check, can be eliminated because when a channel contact input actuates, an immediate alarm will occur. This obviates the needs to monitor these contact inputs as part of channel check.

2.

The trip output signals (Neutron Flux Upscale/Simulated Thermal Power - Upscale/APRM Inoperative/OPRM Upscale) from all four APRM channels go to each of the four APRM 2-out-of-4 voters. Each of the APRM 2-out-of-4 Voters provides an input to one PPS channel (APRM 2oo4 Voter 1 to PPS channel A, APRM 2oo4 Voter 2 to PPS channel B, APRM 2oo4 Voter 3 to PPS channel C and APRM 2oo4 Voter 4 to PPS channel D).

3.

There is one drywell pressure PPS channel comparison vs. multiple as listed in the table. This reflects that the drywell pressure is one function in Table 3.3.1, function 3 in the new technical specifications.

In the case of 4.3.2.1 Function 6h - Drywell Pressure - High/Reactor Pressure - Low, the Reactor Pressure - Low surveillance is covered by the PPS channel comparison application diagnostic.

2.4. Currently, each RHR pump contains redundant transmitters for 4.3.3.1-1 4e. Each Core Spray loop contains a transmitter for 4.3.3.1-1 function 4d. The redundant RHR transmitters are eliminated as part of the Limerick DMP sensor consolidation. Core Spray transmitters are retained. As a result, these single signals will not be subject to a channel check because they each measure a distinct pump pressure. Instrument redundancy elimination is deemed acceptable because their use for ADS pump permissive logic is changing to a voting scheme (1 out of 4 for RHR OR 2 out of 2 for each train of Core Spray) Because the redundant instruments have been eliminated, and the remaining instruments measure a separate parameter, the definition of a channel check is no longer met and these items are removed.

LIM-25-010-NP, Rev. 4 Westinghouse Non-Proprietary Class 3 - Updated Table A.6.1-1

Westinghouse Non-Proprietary Class 3 - Updated Figure 3.4-3 Figure 3.4-3 RPS Trip Functions "ith > 124 m$ Response Time LIM-25-010-NP, Rev. 4 a.c 166

Westinghouse Non-Proprietary Class 3 1 - Clean Figure 3.4-3 LIM-25-010-NP, Rev. 4

]a,c Figure 3.4-3 RPS Trip Functions with > 166 ms Response Time Limerick Generating Station, Units 1 and 2 Docket Nos. 50-352 and 50-353 WEC affidavit for CAW-25-058 for WEC Proprietary Information in Attachment 1 ATTACHMENT 1 TRANSMITTED HEREWITH CONTAINS PROPRIETARY INFORMATION - WITHHOLD UNDER 10 CFR 2.390 When separated, the cover letter, Attachment 2, and Attachment 3 are decontrolled.

Westinghouse Non-Proprietary Class 3 AFFIDAVIT CAW-25-058 Page 1 of 3 Commonwealth of Pennsylvania:

County of Butler:

(1)

I, Jerrod Ewing, Manager, Operating Plants Licensing; Cranberry Township, PA, have been specifically delegated and authorized to apply for withholding and execute this Affidavit on behalf of Westinghouse Electric Company LLC (Westinghouse).

(2)

I am requesting the proprietary portions of LIM-25-010-P, Revision 4 be withheld from public disclosure under 10 CFR 2.390.

(3)

I have personal knowledge of the criteria and procedures utilized by Westinghouse in designating information as a trade secret, privileged, or as confidential commercial or financial information.

(4)

Pursuant to 10 CFR 2.390, the following is furnished for consideration by the Commission in determining whether the information sought to be withheld from public disclosure should be withheld.

(i)

The information sought to be withheld from public disclosure is owned and has been held in confidence by Westinghouse and is not customarily disclosed to the public.

(ii)

The information sought to be withheld is being transmitted to the Commission in confidence and, to Westinghouses knowledge, is not available in public sources.

(iii)

Westinghouse notes that a showing of substantial harm is no longer an applicable criterion for analyzing whether a document should be withheld from public disclosure. Nevertheless, public disclosure of this proprietary information is likely to cause substantial harm to the competitive position of Westinghouse because it would enhance the ability of competitors to provide similar technical evaluation justifications and licensing defense services for commercial power reactors without commensurate expenses. Also, public disclosure of the information would enable others to use the information to meet NRC requirements for licensing documentation without purchasing the right to use the information.

Westinghouse Non-Proprietary Class 3 AFFIDAVIT CAW-25-058 Page 2 of 3 (5)

Westinghouse has policies in place to identify proprietary information. Under that system, information is held in confidence if it falls in one or more of several types, the release of which might result in the loss of an existing or potential competitive advantage, as follows:

(a)

The information reveals the distinguishing aspects of a process (or component, structure, tool, method, etc.) where prevention of its use by any of Westinghouse's competitors without license from Westinghouse constitutes a competitive economic advantage over other companies.

(b)

It consists of supporting data, including test data, relative to a process (or component, structure, tool, method, etc.), the application of which data secures a competitive economic advantage (e.g., by optimization or improved marketability).

(c)

Its use by a competitor would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.

(d)

It reveals cost or price information, production capacities, budget levels, or commercial strategies of Westinghouse, its customers or suppliers.

(e)

It reveals aspects of past, present, or future Westinghouse or customer funded development plans and programs of potential commercial value to Westinghouse.

(f)

It contains patentable ideas, for which patent protection may be desirable.

(6)

The attached documents are bracketed and marked to indicate the bases for withholding. The justification for withholding is indicated in both versions by means of lower-case letters (a) through (f) located as a superscript immediately following the brackets enclosing each item of information being identified as proprietary or in the margin opposite such information. These lower-case letters refer to the types of information Westinghouse customarily holds in confidence identified in Sections (5)(a) through (f) of this Affidavit.

Westinghouse Non-Proprietary Class 3 AFFIDAVIT CAW-25-058 Page 3 of 3 I declare that the averments of fact set forth in this Affidavit are true and correct to the best of my knowledge, information, and belief. I declare under penalty of perjury that the foregoing is true and correct.

Executed on: 10/1/2025 Signed electronically by Jerrod Ewing